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- 2017
- spectral reconstruction
- interference
- polarization
- transform
- imaging spectrometer
- Optoelectronic Information Science and Engineering
- BITTT
- Zhejiang University
- Guilin University of Aerospace Technology
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Contrast-Enhanced Mammography (CEM) for Detecting Residual Disease after Neoadjuvant Chemotherapy: A Comparison with Breast Magnetic Resonance Imaging (MRI)
摘要： Objective. To evaluate the performance of contrast-enhanced mammography (CEM) compared to magnetic resonance imaging (MRI) for estimating residual tumor size after neoadjuvant chemotherapy (NAC) in women with newly diagnosed breast cancer. Methods. The institutional review board approved this study. This prospective study included women with newly diagnosed breast cancer who underwent breast CEM and MRI at the end of the last cycle of NAC and before definitive surgery. Size of residual malignancy on post-NAC CEM and MRI was compared with surgical pathology. Agreements and correlations of CEM and MRI measurements with histological size were assessed. Results. Thirty-three patients were included with a mean age of 45 years (range 22–76). The sensitivity, specificity, and positive and negative predictive value for detection of residual disease of CEM were 76%, 87.5%, 95%, and 86.4%, and those of MRI were 92%, 75%, 92%, and 75%. Comparing CEM to MRI, the mean difference was ?0.8 cm, concordance coefficient was 0.7, and Pearson correlation was 0.7 (p = 0.0003). The concordance coefficient between measurements of each imaging modality and pathologic tumor size was 0.7 for CEM and 0.4 for MRI. Pearson correlation was 0.8 for CEM and 0.5 for MRI. Mean differences between CEM, MRI, and residual histopathological tumor size were 0.8 cm and 1.8 cm, respectively. Conclusions. CEM has good correlation and agreement with histopathology for measuring residual disease after NAC. CEM was comparable to MRI, showing high positive predictive value and specificity for detecting residual disease.
关键词： neoadjuvant chemotherapy,residual disease,magnetic resonance imaging,contrast-enhanced mammography,breast cancer
更新于2025-09-04 15:30:14
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Role of radiologic imaging in genetic and acquired neuromuscular disorders
摘要： Great technologic and clinical progress have been made in the last two decades in identifying genetic defects of several neuromuscular diseases, as Spinal Muscular Atrophy, genetic muscular dystrophies and other genetic myopathies. The diagnosis is usually challenging, due to great variability in genetic abnormalities and clinical phenotypes and the poor specificity of complementary analyses, i.e., serum creatine kinase (CK) and electrophysiology. Muscle biopsy represents the gold standard for the diagnosis of genetic neuromuscular diseases, but clinical imaging of muscle tissue is an important diagnostic tool to identify and quantify muscle damage. Radiologic imaging is, indeed, increasingly used as a diagnostic tool to describe patterns and the extent of muscle involvement, thanks to modern techniques that enable to define the degrees of muscle atrophy and changes in connective tissue. They usually grade the severity of the disease process with greater accuracy than clinical scores. Clinical imaging is more than complementary to perform muscle biopsy, especially as ultrasound scans are often mandatory to identify the muscle to be biopsied. We will here detail and provide examples of the radiologic methods that can be used in genetic and acquired neuromuscular disorders, stressing pros and cons.
关键词： dystrophies,genetic muscle disorders,CT,Muscle Imaging,myopathies,MRI
更新于2025-09-04 15:30:14
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Radiation-responsive scintillating nanotheranostics for reduced hypoxic radioresistance under ROS/NO-mediated tumor microenvironment regulation
摘要： Abstract: Hypoxia-induced radioresistance is the primary reason for failure of tumor radiotherapy (RT). Changes within the irradiated tumor microenvironment (TME) including oxygen, reactive oxygen species (ROS) and nitric oxide (NO) are closely related to radioresistance. Therefore, there is an urgent need to develop new approaches for overcoming hypoxic radioresistance by incorporating TME regulation into current radiotherapeutic strategies. Methods: Herein, we explored a radiation-responsive nanotheranostic system to enhance RT effects on hypoxic tumors by multi-way therapeutic effects. This system was developed by loading S-nitrosothiol groups (SNO, a NO donor) and indocyanine green (ICG, a photosensitizer) onto mesoporous silica shells of Eu3+-doped NaGdF4 scintillating nanocrystals (NSC). Results: Under X-ray radiation, this system can increase the local dosage by high-Z elements, promote ROS generation by X-ray-induced photodynamic therapy, and produce high levels of NO to enhance tumor-killing effects and improve hypoxia via NO-induced vasodilation. In vitro and in vivo studies revealed that this combined strategy can greatly reinforce DNA damage and apoptosis of hypoxic tumor cells, while significantly suppressing tumor growth, improving tumor hypoxia and promoting p53 up-regulation and HIF1α down-regulation. In addition, this system showed pronounced tumor contrast performance in T1-weighted magnetic resonance imaging and computed tomography. Conclusion: This work demonstrates the great potential of scintillating nanotheranostics for multimodal imaging-guided X-ray radiation-triggered tumor combined therapy to overcome radioresistance.
关键词： X-ray induced photodynamic therapy,hypoxia-induced radioresistance,nanoscintillators,multimodal imaging,nitric oxide
更新于2025-09-04 15:30:14
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HIGH-RESOLUTION GRID-INDEPENDENT IMAGING FOR TERAHERTZ 2-D SYNTHETIC APERTURE RADAR WITH SPATIAL UNDER-SAMPLING
摘要： For the purpose of two-dimensional (2-D) imaging in the Terahertz (THz) near field through 2-D synthetic aperture radar technology, Fourier transform (FT) is one of the most popular imaging ways. However, FT-based algorithms would encounter performance loss either when spatial sampling is under Nyquist frequency or there are off-grid scatterers in the scene of interest. Therefore, by exploiting the theory of matrix enhancement and continuous parameter estimation, we propose to use matrix enhancement and matrix pencil (MEMP) method and matched filter to deal with arbitrarily located scatterers when spatial under-sampling is adopted. Through constructing a specifically expanded matrix, the information of the scatterers involved in the small data set can be enhanced. Then, high-resolution grid-independence 2-D imaging can be achieved by the combination of MP and matched filter. Simulation results verify the effectiveness of the proposed algorithm.
关键词： Terahertz,matrix pencil,matrix enhancement,synthetic aperture radar,Fourier transform,grid-independent imaging,under-sampling
更新于2025-09-04 15:30:14
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DYADIC POINT SPREAD FUNCTIONS FOR 3D INVERSE SOURCE IMAGING BASED ON ANALYTICAL INTEGRAL SOLUTIONS
摘要： Imaging is a valuable tool for solving inverse source problems. The achievable image quality is determined by the imaging system. Its performance can be evaluated by using the concept of point spread functions (PSFs). It is common to compute the PSFs using a numerical algorithm. However, in some cases the PSFs can be derived analytically. In this work, new analytical PSFs are presented. The results apply to scalar and dyadic scenarios in 3D originating from acoustics and electromagnetics. Data sets with narrow angular acquisition or complete spherical coverage are considered, where broadband and narrowband frequency domain data is supported. Several visualizations accompany the resulting formulas. Finally, the analytical PSFs are veri?ed using a numerical implementation of the imaging process.
关键词： point spread functions,acoustics,electromagnetics,inverse source imaging,analytical integral solutions
更新于2025-09-04 15:30:14
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The LEECH Exoplanet Imaging Survey: Limits on Planet Occurrence Rates under Conservative Assumptions
摘要： We present the results of the largest L′ (3.8 μm) direct imaging survey for exoplanets to date, the Large Binocular Telescope Interferometer Exozodi Exoplanet Common Hunt (LEECH). We observed 98 stars with spectral types from B to M. Cool planets emit a larger share of their ?ux in L′ compared to shorter wavelengths, affording LEECH an advantage in detecting low-mass, old, and cold-start giant planets. We emphasize proximity over youth in our target selection, probing physical separations smaller than other direct imaging surveys. For FGK stars, LEECH outperforms many previous studies, placing tighter constraints on the hot-start planet occurrence frequency interior to ～20 au. For less luminous, cold-start planets, LEECH provides the best constraints on giant-planet frequency interior to ～20 au around FGK stars. Direct imaging survey results depend sensitively on both the choice of evolutionary model (e.g., hot- or cold-start) and assumptions (explicit or implicit) about the shape of the underlying planet distribution, in particular its radial extent. Arti?cially low limits on the planet occurrence frequency can be derived when the shape of the planet distribution is assumed to extend to very large separations, well beyond typical protoplanetary dust-disk radii (?50 au), and when hot-start models are used exclusively. We place a conservative upper limit on the planet occurrence frequency using cold-start models and planetary population distributions that do not extend beyond typical protoplanetary dust-disk radii. We ?nd that ?90% of FGK systems can host a 7–10 MJup planet from 5 to 50 au. This limit leaves open the possibility that planets in this range are common.
关键词： planetary systems,techniques: high angular resolution,planets and satellites: gaseous planets,stars: imaging
更新于2025-09-04 15:30:14
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Handbook of Advanced Non-Destructive Evaluation || Terahertz Techniques in NDE
摘要： So far, terahertz measurement technology has rarely been used in industry. This book chapter presents therefore the underlying technologies, the resulting possibilities and exemplary applications. The introduction describes the basic properties of terahertz systems and the advantages of terahertz technology over established techniques such as infrared, X-rays and ultrasound. The two industrially relevant terahertz techniques, time domain spectrometer and FMCW system, are described in detail. In addition, the metrological basics for their main applications are introduced. Imaging is required in many applications. Different approaches are presented. Before the chapter concludes with an outlook on future applications, current application examples are discussed. This concerns applications in the fields of coating thickness measurement, safety, materials research, testing of lightweight materials and inline testing. An extensive reference list provides a deeper insight into the topics addressed.
关键词： lightweight materials,materials research,coating thickness measurement,terahertz,NDE,FMCW,imaging,inline testing,time-domain spectroscopy
更新于2025-09-04 15:30:14
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Central serous chorioretinopathy in elderly subjects: angiographic and tomographic characteristics
摘要： Purpose To investigate the angiographic, tomographic, and clinical characteristics of idiopathic central serous chorioretinopathy (CSC) in elderly patients. Methods The patients were divided into two groups according to a cutoff age of 60 years at baseline. Patients underwent spectral domain optical coherence tomography, fluorescein angiography, and indocyanine green angiography. Angiographic and tomographic features were compared between the two groups (young vs. elderly group). Results Of 176 patients, 26 patients (15.1%) were 60 years or older. Complete resolution of subretinal fluid after treatment was noted in 72.0% of the elderly group and 90.8% of the young group (P = 0.021). The elderly group showed worse baseline and final vision, more bilateral involvement, and lower male preponderance than the young group (P < 0.05, respectively). The elderly group was also associated with a higher frequency of retinal pigment epithelium depigmentation, foveal thinning, and double-layer sign compared with the young group (P < 0.05, respectively). Conclusion CSC in elderly patients was associated with a lower resolution of serous detachment, increased impairment of retinal pigment epithelial layers, foveal thinning, and worse visual outcome, suggesting a chronic insult to the choroidal vessels involving more severe damage to the outer retinal layers.
关键词： Pachychoroid,Polypoidal choroidal vasculopathy,Fluorescein angiography,Photo dynamic therapy,Imaging,Optical coherence tomography,Indocyanine green angiography,Central serous chorioretinopathy
更新于2025-09-04 15:30:14
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Far‐Red/Near‐Infrared Emissive (1,3‐Dimethyl)barbituric Acid‐Based AIEgens for High‐Contrast Detection of Metastatic Tumors in Lung
摘要： Despite of the enthusiastic research in aggregation-induced emission luminogens (AIEgens) in recent years, the ones that can be smoothly used for sophisticated biomedical applications such as in vivo bioimaging of pulmonary metastatic tumors during surgery are still limited. Herein, we report the design and synthesis of a new series of fluorescent AIEgens that consist of methoxy-substituted tetraphenylethene (TPE) as the electron-donating moiety, (1,3-dimethyl)barbituric acid as the electron-withdrawing moiety, and different π-bridge units. As compared to benzene or 3,4-ethylenedioxythiophene, using thiophene as the π-conjugation unit between the donor and acceptor results in relatively higher absolute fluorescence quantum yield (14.5%) in water when formulating the corresponding AIEgens into nanoparticles (AIE dots) with amphiphilic co-polymer as the doping matrix. The highly FR/NIR emissive thiophene-based AIE dots are demonstrated to be potent for intraoperative detection of pulmonary metastatic tumors particularly the micro-sized ones with excellent signal-to-background ratio.
关键词： barbituric acid,AIE dot,fluorescence imaging,image-guided cancer surgery,aggregation-induced emission luminogen
更新于2025-09-04 15:30:14
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Label‐Free Metabolic Classification of Single Cells in Droplets Using the Phasor Approach to Fluorescence Lifetime Imaging Microscopy
摘要： Characterization of single cell metabolism is imperative for understanding subcellular functional and biochemical changes associated with healthy tissue development and the progression of numerous diseases. However, single-cell analysis often requires the use of ?uorescent tags and cell lysis followed by genomic pro?ling to identify the cellular heterogeneity. Identifying individual cells in a noninvasive and label-free manner is crucial for the detection of energy metabolism which will discriminate cell types and most importantly critical for maintaining cell viability for further analysis. Here, we have developed a robust assay using the droplet micro?uidic technology together with the phasor approach to ?uorescence lifetime imaging microscopy to study cell heterogeneity within and among the leukemia cell lines (K-562 and Jurkat). We have extended these techniques to characterize metabolic differences between proliferating and quiescent cells—a critical step toward label-free single cancer cell dormancy research. The result suggests a droplet-based noninvasive and label-free method to distinguish individual cells based on their metabolic states, which could be used as an upstream phenotypic platform to correlate with genomic statistics.
关键词： single cell analysis,metabolism,circulating tumor cells,droplet micro?uidics,?uorescence lifetime imaging microscopy,phasor analysis,quiescent stage
更新于2025-09-04 15:30:14